Fix lint and unit tests

metadata.yaml

@@ -5,7 +5,7 @@ description: |
  OpenStack Compute, codenamed Nova, is a cloud computing fabric controller. In
  addition to its "native" API (the OpenStack API), it also supports the Amazon
  EC2 API.
-categories:
+tags:
   - openstack
 provides:
   cloud-compute:

unit_tests/test_nova_compute_utils.py

@@ -731,6 +731,7 @@ class NovaComputeUtilsTests(CharmTestCase):
             group='root',
             nr_hugepages=488,
             mount=False,
+            set_shmmax=True,
         )
         check_call_calls = [
             call('/etc/init.d/qemu-hugefsdir'),
@@ -752,6 +753,7 @@ class NovaComputeUtilsTests(CharmTestCase):
             group='root',
             nr_hugepages=2048,
             mount=False,
+            set_shmmax=True,
         )
 
     @patch('psutil.virtual_memory')